Is there a relationship between dopamine and rhegmatogenous retinal detachment?

Potential therapeutic strategies for photoreceptor degeneration: the path to restore vision

Photoreceptors (PRs), as the most abundant and light-sensing cells of the neuroretina, are responsible for converting light into electrical signals that can be interpreted by the brain. PR degeneration, including morphological and functional impairment of these cells, causes significant diminution of the retina's ability to detect light, with consequent loss of vision. Recent findings in ocular regenerative medicine have opened promising avenues to apply neuroprotective therapy, gene therapy, cell replacement therapy, and visual prostheses to the challenge of restoring vision. However, successful visual restoration in the clinical setting requires application of these therapeutic approaches at the appropriate stage of the retinal degeneration. In this review, firstly, we discuss the mechanisms of PR degeneration by focusing on the molecular mechanisms underlying cell death. Subsequently, innovations, recent developments, and promising treatments based on the stage of disorder progression are further explored. Then, the challenges to be addressed before implementation of these therapies in clinical practice are considered. Finally, potential solutions to overcome the current limitations of this growing research area are suggested. Overall, the majority of current treatment modalities are still at an early stage of development and require extensive additional studies, both pre-clinical and clinical, before full restoration of visual function in PR degeneration diseases can be realized.

Dopamine Receptor Signaling Regulates Fibrotic Activation of Retinal Pigmented Epithelial Cells

Retinal pigmented epithelial (RPE) cells play an important role in retinal fibrotic diseases such as proliferative vitreoretinopathy (PVR). The purpose of this study was to elucidate the involvement of dopamine receptor signaling in regulating the fibrotic activation of RPE cells. Dopamine receptor expression, the effect of dopamine on fibrotic activity, and dopamine production were measured in the human RPE cell line ARPE-19. The fibrotic activation of RPE cells was evaluated in response to treatments with selective dopamine receptor agonists and antagonists by measuring gene expression, migration, proliferation, and fibronectin deposition. DRD2 and DRD5 are the dominant dopaminergic receptors expressed in ARPE-19 cells and TGFβ stimulates enhances autocrine release of dopamine which we show further exasperates fibrotic activation. Finally, treatment with D2 dopamine receptor antagonists or D5 dopamine receptor agonists inhibits profibrotic gene expression, migration, proliferation, and fibronectin deposition and thus may serve as effective mechanisms for treating retinal fibrosis including PVR.

Optical Coherence Tomography findings in patients with Multiple Substance Use Disorder

OBJECTIVE

Optical Coherence Tomography (OCT) is a relatively new diagnosis method displaying biological tissue layers by with high-resolution sections. In the present study, the purpose was to examine the OCT findings of patients with Multiple Substance Use Disorder (MSUD) by comparing these findings with healthy controls.

METHODS

The study included 30 MSUD and 30 controls. Detailed biomicroscopic examinations were carried out for all participants, and intraocular pressure, followed by OCT. The central macular thickness (CMT), mean macular thickness (MMT), mean macular volume (MMV), and retinal nerve fibre layer thickness (RNFL) were measured by using OCT.

RESULTS

It was determined that the MMT and CMT were thinned in both eyes compared to the healthy controls. The MMV was decreased in both eyes in patients with substance use disorders compared to healthy controls. The RNFL and total thickness were thickened in temporal and inferior parts in patients with MSUD in both eyes compared to healthy. In the superior quadrant, thickening was detected only in the left eye.

CONCLUSIONS

Based on our results obtained here, it was concluded that vision-related findings should be carefully questioned and evaluated when treatment is planned for patients with substance use.